1. Field of the Invention
The present invention generally relates to a system including an endoscope having an insertion section to be inserted into a cavity under inspection and an operation section to which a proximal end of the insertion section is connected, and a disposable protection cover having an insertion section cover for covering the insertion section of the endoscope, an operation section cover for covering the operation section of the endoscope, and at least one conduit channel extending within the insertion section cover.
2. Description of the Related Art
An endoscope system has been widely utilized for providing diagnostic and therapeutic indications for coeliac cavities of patients and for internal inspection of mechanical structures. To this end, various kinds of endoscopes have been developed. For instance, in order to inspect or treat the oesophagus, stomach and duodenum, upper endoscopes have been utilized. Further, colonoscopes have been developed to examine colons, and sigmoidoscopes have been proposed to inspect rectums and sigmoid colons. When the endoscope is used, an insertion portion of the endoscope has to be inserted into a cavity of a patient, so that the outer surface of the insertion section of the endoscope becomes contaminated with living tissues and liquids. Such a contaminated endoscope can not be successively used for patients. Therefore, once the endoscope is used to diagnose and/or treat a patient, it is necessary to clean and sterilize the endoscope. Of course, the cleaning of the endoscope requires a substantial amount of time, and during this cleaning time, it is impossible to perform endoscopic procedures using this endoscope. In order to mitigate such an idle time, it is necessary to prepare a large number of endoscopes. However, endoscopes are rather expensive, so that it is practically difficult to prepare a large number of endoscopes, particularly in a small hospital or clinic. Therefore, in almost all hospitals and clinics, in practice, after the endoscope has been used for examining or treating a patient, the endoscope is immediately cleaned. Typically, this cleaning requires several minutes to ten minutes. In order to effect the complete washing and sterilization, the cleaning has be to performed for several tens of minutes.
Further, the endoscope has various channels such as an air channel, a water channel, a suction channel, and a forceps channel which extend along the insertion section from a proximal end to a distal end thereof, and these channels, except the forceps channel, are connected via tubes to respective devices such as an air supply pump, a water supply pump, a water suction pump and an air suction pump. These channels are subjected to contact with living tissues and liquids. However, in order to clean these channels of the endoscope completely, a relatively long time is required. Thus, the endoscope can not be utilized efficiently for the long cleaning time. In a large hospital or clinics, a large number of endoscopes may be prepared in order to mitigate the problem of cleaning time. However, this solution results in an increase in operating costs. Further, in small clinics, it is practically impossible to prepare a number of expensive endoscopes.
Moreover, the endoscope might be broken during cleaning and the usable life of the endoscope is liable to be shortened by the cleaning.
In order to avoid the above-explained various problems, there has been proposed an endoscope system, in which the endoscope is covered with a disposable protection sheath-like cover having channels formed therein. For instance, U.S. Pat. Nos. 4,721,097, 4,741,326, 4,825,850, 4,869,238, 4,991,564, 4,991,565, 5,050,585 disclose various kinds of disposable protection sheath-like covers having channels formed therein. In U.S. Pat. No. 4,646,722, there is shown an endoscope system in which the endoscope is covered with a protection sheath, while a tube having channels formed therein is inserted into a U-shaped cutout formed in an outer surface of the endoscope along a longitudinal axis thereof. Upon diagnosis, the insertion section of the endoscope is covered with the protection sheath, and after the inspection, the sheath is removed from the insertion section and is then discarded. Therefore, it is no longer necessary to clean the endoscope after every inspection.
In the above-mentioned U.S. Patents, the protection sheath-like cover is constructed to cover only the insertion section of the endoscope, but does not cover an operation section of the endoscope. It should be noted that the operation section of the endoscope is handled by doctors and operators, and thus is brought into contact with the living tissues and liquids of a patient. Therefore, in order to remove the contamination of the operation section of the endoscope due to such living tissues and liquids, it is advantageous to cover not only the insertion section, but also the operation section of the endoscope.
In European Patent Publication No. 0 349 479 A1, there is disclosed an endoscope system, in which not only the insertion section, but also the operation section of the endoscope are covered with a disposable protection cover. That is to say, the protection cover comprises a sheath-like portion for covering the insertion section of the endoscope and a bag-like portion for covering the operation section, the sheath-like portion and bag-like portion being integrally formed. The operation section of the endoscope is usually provided with various operating members such as angle knobs and optical system adjusting members. The endoscope shown in the above mentioned European Patent Publication No. 0 349 479 A1 is of a colonoscope type, so that angle knobs are not provided. However, a focus adjusting ring is provided, which has to be operated during the inspection. To this end, an aperture is formed in the bag-like portion of the protection cover at a position corresponding to the focus adjusting ring. In this case, in order to operate the ring easily, it is preferable to form a large aperture. However, contamination via the aperture is liable to be large.
In order to avoid such a drawback, in European Patent Publication No. 0 341 719 A1, there is proposed another known endoscope system, in which an insertion section of an endoscope is covered with a disposable protection sheath-like cover, and an operation section of the endoscope is covered with a disposable protection bag-like cover which is mated or joined with the protection sheath-like cover in order to prevent contamination through the junction of the sheath-like cover and the bag-like cover. In this known endoscope system, angle knobs are detachably secured to a shaft extending from a housing of the operation section. The shaft protrudes from the protection bag-like cover through an aperture formed therein. Since a diameter of the shaft is much smaller than a diameter of the angle knobs, a size of the aperture can be made much smaller than the angle knobs. Therefore, a possibility of contamination via the aperture formed in the bag-like cover can be reduced as compared with a case in which a large aperture, through which the angle knobs are projected from the bag-like cover, is formed in the bag-like cover.
However, in typical endoscopes, angle knobs for moving the distal end of the insertion section in the up and down directions as well as in the right and left directions are secured to the shaft, and it is not necessary to remove the angle knobs from the shaft during the usual usage. Therefore, in the known endoscopes, the couplings of the angle knobs with the shaft are effected in various ways, and a set of angle knobs destined for a certain endoscope can not be secured to a shaft of another endoscope. In the usual endoscopes, this does not cause any problem, because the angle knobs and shaft are not usually decoupled from each other. However, in the endoscope system disclosed in the above-cited European Patent Publication No. 0 341 719 A1, this results in a serious problem. In an endoscopic procedure area, various different types of endoscopes are arranged, and therefore, once the angle knobs are removed from the shaft extending from the operation section of the endoscope, it is not easy for users to select the correct angle knobs. If angle knobs which are not mated with a shaft of an operation section of a particular endoscope are forcibly secured to this shaft, the angle knobs and/or shaft might be broken.
In a system including an endoscope and a disposable protection cover, if a pin hole is formed in the sheath-like cover, contamination arises via the pin hole. In order to avoid such a problem, respective protection sheath-like covers have to be checked in a factory, and only sheath-like covers which have been checked to have no pin hole are shipped or forwarded. However, the known sheath-like covers are not formed such that such a pin hole check can be performed easily, so that in practice, pin hole checking has not been performed. Therefore, there is a danger that a protection sheath-like cover having a pin hole will be used for the endoscopic procedure. Therefore, it is preferable to effect the pin hole check at the factory as well as at the endoscopic procedure site in a positive and easy manner. However, in the known system disclosed in the above-mentioned prior art references, this pin hole check can not be carried out easily.
Further, in known endoscope systems using disposable protection sheath-like covers, various conduit channels are provided within the cover. In practice, these conduit channels are formed by flexible tubes, and these tubes are extended within the cover from a proximal end to a distal end thereof. At these proximal and distal ends, these tubes are fixed to construction members made of rather rigid material so that they can assume predetermined positions at these ends. However, substantial portions of the tubes except for the proximal and distal ends thereof are not fixed, but are extended freely. Usually these tubes have a circular cross section, and thus relatively large spaces are formed between these tubes. Therefore, when the insertion section is bent by suitably operating the angle knobs, one or more tubes might move relatively largely. Then, the tubes might resist the smooth bending movement of the insertion section, and the distal end of the insertion section might not be directed in a desired direction, but might be bent in a direction which is different from the desired direction. As is readily apparent, this causes a problem in handling the endoscope during the inspection.